Because the pump is designed according to the impurity fluid, the structure of the pump is more reasonable. Compared with the impurity pump designed based on the theory of clear water fluid in the past, it is more energy-saving when conveying solid-liquid two-phase media.
The impeller of axial flow pump is equipped with 2 ~ 7 blades, which rotate in the cylindrical pump shell. The fixed guide vanes are installed on the pump casing at the upper part of the impeller to eliminate the rotary motion of liquid, convert it into axial motion, and convert the kinetic energy of rotary motion into pressure energy. Axial flow pumps are usually single-stage, and a few are made into two-stage pumps. The flow range is very large, from 180 to 3.6 million cubic meters per hour; The lift force is generally below 20 meters. Axial flow pumps are generally vertical, with the impeller submerged under water, and there are also horizontal or inclined axial flow pumps. When the impeller of a small axial-flow pump is installed above the water surface, it needs to be started by exhausting and pumping water with a vacuum pump. The blades of axial flow pump are divided into fixed and adjustable structures. In the operation of large axial flow pump, the working conditions (mainly flow) often need to change greatly. Adjusting the installation angle of blades can keep the pump running in high efficiency area under different working conditions. The blade installation angle of small pump is generally fixed. Axial flow pump is one of the power pumps with the highest specific speed, which is 500 ~ 1600. The flow head and flow shaft power characteristic curve of the pump are steep in the small flow area, so it should be avoided to run in this unstable small flow area. The axial power of axial flow pump is maximum at zero flow, so the valve on the discharge pipeline must be opened before starting the pump to reduce the starting power. Axial flow pump is mainly suitable for low-lift and large-flow occasions, such as irrigation, drainage, wharf drainage, water level adjustment of canal lock, or as a large circulating pump of power plant. High-lift axial flow pump (made into two stages if necessary) can be used for water jet propulsion of shallow water ships.